More than off-task: Increased freely-moving thought in ADHD

Disentangling racing thoughts from mind wandering in adult attention deficit hyperactivity disorder

Introduction

Mental restlessness reported by adult with Attention Deficit Hyperactivity Disorder (ADHD) has been mainly explained by excessive mind wandering. However, the description of a mind constantly on the go is also akin to racing thoughts, predominantly described in bipolar disorder. This paper aimed at disentangling mind wandering from racing thoughts in adult with ADHD. Associations between those mental phenomena and the ADHD symptomatology were also investigated.

Methods

To this aim, 84 adults with ADHD completed self-reported questionnaires, including the Mind Wandering-Deliberate and Mind Wandering-Spontaneous questionnaires, the Racing and Crowded Thoughts Questionnaire and the Daydreaming Frequency Scale. Factorial analysis and multiple linear regressions were performed.

Results

The factor analysis yielded a two-factor solution. The first factor encompassed the three facets of racing thoughts and was predicted by emotional lability. The second comprised deliberated-MW, spontaneous-MW and daydreaming, but was neither related to the ADHD symptoms, nor functional impairment.

Discussion

These findings suggest that MW and racing thoughts are two distinguishable mental phenomena. Racing thoughts appear to be a relevant hypothesis to explain the mental restlessness in adult ADHD.

Beyond mind wandering: Performance variability and neural activity during off-task thought and other attention lapses

To study the characteristics of attention lapses, a metronome response task and experience sampling were employed while recording fMRI data. Thought prompts queried several attention states (on-task, task-related interference, off-task, inattention). Off-task thoughts were probed on whether they arose in a spontaneous or constrained (i.e., directed) manner. Increased fMRI activation was observed in the default mode network during off-task thought and in subregions of the anterior cingulate cortex and inferior frontal gyrus during inattention. Activation also increased in the left hippocampus during constrained thoughts. Functional connectivity increased between the left superior temporal sulcus and right temporoparietal junction for constrained compared to spontaneous thoughts. Overall, behavioral results indicated a monotonic increase in performance variability from on-task to inattention. However, subtle but consistent differences were observed between self-reported attention state and performance. Results are discussed from perspectives of mind wandering frameworks, the function of brain networks, and the role of engagement in off-task thought.

Development and validation of children's mind wandering scales

Introduction

Mind wandering is generally considered an endogenous mental state that arises spontaneously, which is one of the most common experiences of consciousness and typically occurs at a significant cost to mental health and behavioral performance. Previous studies have shown that mind wandering appears to be a stable trait and can be assessed reliably in adults. Surprisingly little, however, is known about how to measure the frequency of mind wandering in children, given that children can accurately introspect their experiences. The present studies aimed to develop the Frequency of Children's Mind Wandering Scale (CMWS-F) and the Context of Children's Mind Wandering Scale (CMWS-C) to assess the frequency of mind wandering and contexts in which mind wandering occurs for children aged 8 to 11 years.

Methods

The exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to develop the CMWS-F and CMWS-C. To further assess the validity of the scales, we compared the scores in CMWS-F/CMWS-C and the frequencies of probe-caught mind wandering in the typical tasks.

Results

In study 1a, the EFA (n = 292) and CFA (n = 346) showed that attentional failure and spontaneous thinking were the two main dimensions of CMWS-F. In study 1b, contexts about mind wandering in children could be divided into high-demand and low-demand contexts using EFA (n = 258) and CFA (n = 347). Study 2 showed moderate positive correlations between the frequencies of probe-caught mind wandering in the tasks and the scores in the scales.

Discussion

The results showed that scores on the two scales could predict the performance on the experimental tasks and further demonstrated empirical validity of the CMWS-F and CMWS-C scales. Taken together, the results of the current studies provided preliminary evidence for the validity and reliability of CMWS-F and CMWS-C in children, which can be used as a reference to balance its downsides and productive aspects of mind wandering.

Prefrontal contributions to the stability and variability of thought and conscious experience

The human prefrontal cortex is a structurally and functionally heterogenous brain region, including multiple subregions that have been linked to different large-scale brain networks. It contributes to a broad range of mental phenomena, from goal-directed thought and executive functions to mind-wandering and psychedelic experience. Here we review what is known about the functions of different prefrontal subregions and their affiliations with large-scale brain networks to examine how they may differentially contribute to the diversity of mental phenomena associated with prefrontal function. An important dimension that distinguishes across different kinds of conscious experience is the stability or variability of mental states across time. This dimension is a central feature of two recently introduced theoretical frameworks-the dynamic framework of thought (DFT) and the relaxed beliefs under psychedelics (REBUS) model-that treat neurocognitive dynamics as central to understanding and distinguishing between different mental phenomena. Here, we bring these two frameworks together to provide a synthesis of how prefrontal subregions may differentially contribute to the stability and variability of thought and conscious experience. We close by considering future directions for this work.